Introduction: Antisocial behaviour is an important adverse outcome of ADHD. The aim of this review is to examine what is known about the clinical, genetic and environmental factors that contribute to the link between ADHD and antisocial behaviour.
Methods: Electronic literature searches for the years 1980-2004 and examination of key reference books were undertaken.
Results: ADHD symptom severity and pervasiveness predict the development of antisocial behaviour. Genetic factors contribute substantially to the risk of developing both problems, although specific genes that influence the development of antisocial behaviour in ADHD have yet to be identified. Some of these genetic effects may be indirectly mediated through environmental risk (gene-environment correlation) or by increasing individual susceptibility to specific environmental adversity (gene-environment interaction). Antisocial behaviour in children with ADHD is also linked with family adversity as well as peer rejection, although some of this adversity may arise as a result of the child's symptoms.
Conclusion: Despite the increased risk of antisocial outcomes in those with ADHD, relatively little is known about what risk factors and mechanisms contribute to the link between both these problems. Given the need for appropriate intervention and prevention strategies and targeting resources, more research is needed in this area.